1. Field of the Invention
The present invention relates to an improvement in a tool gripper for use in a tool rack type magazine for feeding a number of various kinds of tools into an automatic tool exchanger of a machine tool.
2. Description of Related Art
In machine tools, tools for intended machining works are fed by an automatic tool exchanger, and, for instance, a tool rack type magazine that stores tools is employed in such an automatic tool exchanger. In this tool rack type magazine, the tools are held by arm portions of tool grippers which are arranged in vertical and horizontal directions so that a tool that has been used in the machine tool is exchanged by another tool stored in the magazine by moving a tool carrying device in the vertical and horizontal directions. Generally, a tool exchanger is designed so as to allow the tools to be taken in and out in horizontally lateral directions; accordingly, in the prior art, so as to prevent the tools from falling off, ball plungers are disposed in the vicinity of tool entrances of the arm portions of the tool grippers. Turn-preventive keys are also used for the same purposes. The tool grippers of the prior art as described above are obtained by a plurality of gripper unit plates. The gripper unit plates each having arm portions on its right and left sides are sequentially fixed on a column so as to be arranged in the vertical direction.
In the above-described prior art gripper, each of the gripper unit plates is machine-worked so as to form the arm portions on both sides, and then such plates are mounted on a column. Since such a tool rack type magazine is used in order to store a great number of tools, the number of the parts used tends to be large; as a result, it requires a great number of working and assembling steps. Accordingly, the manufacturing costs also tend to be high.